#!/usr/bin/env python3
#
# meteo_ftp.py --- download Meteorological Data via FTP
#                   See HYSPLIT Tutorial Sec 3.2
#
# Change history:
# 10 May 2025 (BB) - initial, cross-platform version

import os
import sys
import platform
from pathlib import Path
import subprocess
import webbrowser

if sys.version_info < (3, 8):
    print("Please use Python 3.8 or higher.")
    sys.exit(1)

system = platform.system().lower()
if system == "windows":
    PGM = Path(sys.argv[1]) if len(sys.argv) > 1 else Path("C:/hysplit")
    OUT = Path(sys.argv[2]) if len(sys.argv) > 2 else PGM / "working"
    DSP = sys.argv[3] if len(sys.argv) > 3 else "YES"
    TTR = Path(os.environ.get("TTR", "C:/Tutorial"))
    exe_suffix = ".exe"
else:
    PGM = Path(sys.argv[1]) if len(sys.argv) > 1 else Path.home() / "hysplit"
    OUT = Path(sys.argv[2]) if len(sys.argv) > 2 else PGM / "working"
    DSP = sys.argv[3] if len(sys.argv) > 3 else "YES"
    TTR = Path(os.environ.get("TTR", Path.home() / "tutorial"))
    exe_suffix = ""

if not PGM.exists():
    script = Path(__file__).name if "__file__" in globals() else "parm_case.py"
    print(f"ERROR: HYSPLIT not found at {PGM}")
    print(f"""
Please specify the path to your HYSPLIT installation using a command-line argument:

python {script} YOUR_HYSPLIT_DIRECTORY [OUT] [DSP (YES|NO)]

Example:
    python {script} C:\\hysplit C:\\hysplit\\working YES
""")
    sys.exit(1)

if not TTR.exists():
    print(f"ERROR: HYSPLIT tutorial not found at {TTR}")
    print("""
Please set the TTR environment variable to point to your HYSPLIT tutorial directory.

For Windows users (Command Prompt):
   SET TTR=YOUR_HYSPLIT_TUTORIAL_DIRECTORY

For Linux users (bash shell):
   export TTR='YOUR_HYSPLIT_TUTORIAL_DIRECTORY'

For Linux users (csh or tcsh shell):
   setenv TTR 'YOUR_HYSPLIT_TUTORIAL_DIRECTORY'
""")
    sys.exit(1)

# Work from OUT
os.chdir(OUT)

#!/usr/bin/env python3
#
# get_reanal.py --- download a monthly global reanalysis file
#                   from the NOAA ARL FTP server
#
# Change history:
# 27 Sep 2026 - initial, cross-platform version translated from batch script

import os
import sys
import platform
from ftplib import FTP, all_errors
from pathlib import Path

if sys.version_info < (3,8):
    print("Please use Python 3.8 or higher.")
    sys.exit(1)

# Detect OS and handle CLI args or fallback defaults
system = platform.system().lower()
if system == "windows":
    PGM = Path(sys.argv[1]) if len(sys.argv) >= 2 else Path("C:\\hysplit")
    OUT = Path(sys.argv[2]) if len(sys.argv) >= 3 else PGM / "working"
else:
    PGM = Path(sys.argv[1]) if len(sys.argv) >= 2 else Path.home() / "hysplit"
    OUT = Path(sys.argv[2]) if len(sys.argv) >= 3 else PGM / "working"

# Verify required paths
if not PGM.exists():
    script = Path(__file__).name if "__file__" in globals() else "get_reanal.py"
    print(f"ERROR: HYSPLIT not found at {PGM}")
    print(f"""
Please specify the path to your HYSPLIT installation using a command-line argument:

python {script} YOUR_HYSPLIT_DIRECTORY [OUT]

Example:
    python {script} C:\\hysplit C:\\hysplit\\working
""")
    sys.exit(1)

if not OUT.exists():
    print(f"ERROR: Output directory not found at {OUT}")
    sys.exit(1)

os.chdir(OUT)

# Set parameters
syr, smo = "1983", "09"
data = f"RP{syr}{smo}.gbl"

host = "ftp.arl.noaa.gov"
user, passwd = "anonymous", "name@server.com"
remote_dir = "/pub/archives/reanalysis"

local_file = OUT / data

# Download file (binary mode)
print("Starting FTP ...")
try:
    with FTP(host) as ftp:
        ftp.login(user=user, passwd=passwd)
        ftp.cwd(remote_dir)
        with open(local_file, "wb") as f:
            ftp.retrbinary(f"RETR {data}", f.write)
except all_errors as e:
    print(f"ERROR: FTP transfer failed -> {e}")
    if local_file.exists() and local_file.stat().st_size == 0:
        local_file.unlink()
    sys.exit(1)

print(f"Completed transfer {data}")

input("Press Enter to continue . . .")